Buffing machine



Nov. 9, 1937. G. E. MCLAUGHLIN ET AL BUFFING MACHINE Original Filed June5, 1936 Patented Nov. 9, 1937 UNITED STATES PATENT OFFICE BUFFINGMACHINE George E. McLaughlin, Broughton, Peabody,

Salem, and Winn E.

Mass., assignors to The Turner Tanning Machinery Company, Portland,Maine, a corporation of Maine 8 Claims.

This invention relates to machines for operating upon hides, skins andleather. While the invention is illustrated with reference to a machinefor buffing leather surfaces it will be understood that the inventionand various important features thereof may have other applications anduses.

This application is a division of a co-pending application Serial No.83,718, filed June 5, 1936, in the names of George E. McLaughlin andWinn E. Broughton.

It is an object of the invention to improve various features of buffingmachines and particularly to facilitate presentation of pieces of workto the bufling roll. It is a further object of the invention to provideimproved means for preventing work pieces from being drawn into suctionmeans provided to remove dust produced by the buffing operation, and atthe-same time to facilitate the removal of dust from the bufiing roll.

To these ends, and in accordance with an important feature of theinvention, there is provided a work supporting roll movable toward andfrom 25 a buffing roll in an organization wherein the work supportingroll is driven by means controlled by a treadle mechanism so arrangedthat the driving means for the roll becomes operative to effect rotationof the latter just before the roll presents the work piece to thebufling roll. The purpose of this arrangement is to secure buffing ofthe surface of a work piece while the latter is moving at apredetermined rate to insure uniformity in the product. Conveniently,the work support- 35 ing roll is at the upper end of a member which ispivoted on a horizontal axis about midway of the length of said member,the roll being driven by a chain in engagement with a sprocket wheelconnected to the shaft of the roll and also with 40 a sprocket wheel insuch relation to the lower end of said member as to permit swinging ofthe member while the driving chain is in place and in operative relationto its driving means. As shown, the chain is driven by a sprocket on a45 shaft which carries rotatably mounted thereon a driving pulleyadapted to be clutched to the shaft through the operation of a treadlemechanism which also effects movement of the work supporting roll indirections toward and from the bumng 50 roll.

Preferably and as shown, there is provided a brush roll rotatable incontact with the surface of the buffing roll to remove dust from theabrasive covering of the latter and to prevent a work 55 piece fromclinging to the bufiing roll and, from being drawn into a suction meansprovided to carry away the dust of the buffing operations. Conveniently,said brush roll has rows of bristles spaced apart in the direction ofthe circumference of the roll such distances that during rota- 5 tion ofthe brush roll an adjacent opening into a suction conduit will bepractically unobstructed at regular intervals by said roll, therebyfacilitating entrance of dust-laden air into the suction means by whichsuch air is drawn away from 10 the buffing cylinder. If desired thebrush roll may be located to brush the surface of a buffed piece ofwork, a member being provided to back the work piece against the thrustof the brush 1 roll. 5

These and other important features of the invention and novelcombinations of parts will now be described in detail in thespecification and then pointed out more particularly in the appendedclaims.

In the drawing,

Fig. 1 is a view in side elevation, and partly in section, of a bufflngmachine;

Fig. 2 is a sectional view taken along the line II ]I of Fig. 1; andFig. 3 is a detail view of a clutch mechanism arranged to be operated bythe treadle shown in Fig. 1.

In the illustrated machine, which is specially designed for performingbufling operations upon tanned hides and skins, there are provided worksupporting rolls 2 and 4 mounted for rotation in the upper end of a pairof swing arms, one of which is shown at 6 in Fig. 1, the said swing armsbeing mounted for oscillation upon a shaft 8 carried by the frontstandard of the machine frame It]. Means is provided under control of atreadle l2 for moving the work supporting rolls 2 and 4 between an openor work receiving position and a work presenting position with respect40 to a buifing roll l4 and its abrasive sheetl covering l5. Enclosingthe larger part of the buffing cylinder 14 is a hood member l6 and alarger hood member H which together form part of an air suction devicerepresented in general by reference character IS, the purpose of saiddevice being to draw off from the neighborhood of the buffing roll 14all of the dust-laden air which results from the bumng operations. Thesuction device by removing the dust helps to keep the abrasive sheetfreer from dust than it otherwise would be. Located below the buffingroll or cylinder I4 is a brush roll 28 positioned adjacent to the loweropening into the air suction device to prevent the work piece from beingdrawn around the builing roll 14 and into the air-suction device. Thisbrush roll also cleans the abrasive sheet II and thus gives it a longerlife. I

he buillng roll I4 is preferably of that type. wherein the abrasivesheet material I 5 is wrapped around the roll and secured thereto byhaving its ends passed through an inclined slot in the cylindrical wallof the roll and into engagement with clamping means constructed andarranged to maintain the abrasive sheet material properly tensioned uponthe cylindrical surface of the roll I4, as fully described in the saidcopending application.

As stated above, the brush roll 20 operates to prevent wrapping of apiece of work about the bufflng cylinder I4, and at the same timeinsures that the work piece will not be drawn into the suction deviceI0. its bristles or brush portions arranged in parallel rows spacedsubstantial distances from each other so that air may at certain timespass freely into a lower entrance 92 of the air-suction device I0. It isto be understood that this free passage of dust-laden air takes place atintervals during the relatively slow rotation of the brush roll 20,

the passage to the entrance 02 being exposed each time that a spacebetween two adjacent rows of bristles reaches a position slightly beyondthe position of the roll shown in Fig. 1. Each of the parallel rows ofbristles presents a straight bladelike edge surface inwiping down anyadvancing edge of the work piece which might otherwise hug the abrasiveroll and enter the suction system, it being noted in this connectionthat the roll 20 rotates in a direction the same as that of the abrasiveor bufllng roll I4, as indicated by the arrows in Fig. 1 of the drawing,whereby the upper surface of the brush roll 20 moves in a direction thereverse of the adjacent lowersurface of the bufnng roll I4. Uponinspection of Fig. 1, it will be observed that the brush roll 20 is of adiameter such as to preclude the possibility of a work piece passingaround the lower periphery of the brush roll and into the open end 02 ofthe air suction device I 0. As shown, the diameter of the brush roll isabout double the corresponding dimension of the opening 02.

If desired, the brush roll 20 may also be positioned to brush thesurface of the work which is undergoing bumng operations. For thispurpose the work support, including the swing arms 0, is provided with aplate 04 to back the depending portion of the workpiece while the brushroll 20 is operating thereon, it being understood that the brush roll isadjusted to the left in Fig. 1 to the desired position to perform abrushing operation on the work. With this function in mind, the

0 brush roll 20 is mounted upon a pair of arms one of which is shown at00 mounted rotatably upon a stud 00 carried by a plate I 00, the rear ofeach arm 00 being provided with a slot I02 arcuate with respect to acenter at the axis of the stud 00. A second stud I04 secured to plateI00 is located in said slot I02. Upon tightening a nut I00 upon theouter end of the stud I04 the arm 00 is secured in the adjusted positionshown in Fig. 1. As

clearly indicated in Figs. 1 and 2, the plate I00 is adjustably securedto the frame ll of the machine by threaded bolts I00 in a slot H0 in theplate I00, proper manipulation of the nuts on said bolts I00 being allthat is necessary to permit adjustment of the plate I00 in a horizontaldirection toward the front of the machine so that the brush roll 20 mayoperate upon portions of the work piece while the latter is backed bythe plate 04.

As shown, the brush roll 20 has When this adjustment of the plate I00 ismade, it is also necessary to swing the arms 00 in an upward directionthrough proper manipulation of the nut I 00 on the bolt I04. It will benoticed that the brush roll 20 is rotated counterclockwise to direct thework piece downwardly in a direction away from the buffing roll I4.Since the-primary function of the brush roll 20 is to prevent improperdisplacement of the work piece, the said roll must be adjusted in anupward direction into properly spaced relation with respect to thesurface of the bumng roll at the same time that it is made to co-operatewith the backing plate 04. If desired, the brush roll 20 may be left inthe position shown in Fig. 1 and a separate roll provided for brushingdust from the surface of the work piece in co-operation with the plate04 As pointed outabove, the work supporting rolls 2 and 4 are movablebetween an open or work receiving position and a closed or workpresenting position with respect to the buffing roll I 4. This movementof the work supporting rolls is secured through proper operation of thetreadle I2 during which a toggle comprising links H4 and H0 isstraightened to the position shown inFig. 1 to bring the roll 4 intowork presenting position relative to the bumng roll I4. As shown, thelink H4 is pivoted at IIO to a member I20 which is screw threaded into apart I22 common to the two swing arms 0. Through proper adjustment ofthe screw threaded member I20, it is possible to vary the distancebetween the roll 4 and the bufling roll I4 in accordance with variationsin the thickness dimensions of different lots of work.

Preferably, and as shown, the work supporting rolls 2 and 4 arepositively driven to feed a work piece into the machine for the bumngoperation.

ries looselya-pulley I40 arranged to be driven con- 7 tinuously by meansof a belt I41 from a power shaft I50. For clutching the shaft I45 to thepu1- ley I40 there is provided a clutch mechanism, shown generally atI40 in Fig. 3, which is arranged to be operated by yoke I40 on a bellcrank lever IOI connected by a long link I 02 to an arm I54 extending upfrom and rigidly connected to the treadle l2, the said rod I52 passingloosely through an opening in the arm I04 and having on its free end aspring I50, the arrangement being such that, upon depressing a treadportion I50 of the treadle I2, the clutch I40 is thrown in to causedriving of the work supporting rolls 2 and 4 just before the roll 4reaches work presenting position with respect to the bufling roll I4.Conveniently there are provided work supporting plates I00 and I02 inassociation with the rolls 2 and 4.

As illustrated, the suction device I0 comprises not only the hoodmembers I0 and I1 but also a conduit I10 which leads to anenclosed-blower (not shown). To insure removal of all of the dust-ladenair there is provided also a supplemcntaryv conduit I12 which leads toan opening at I14 in a sheet metal pocket I10 into which the dependingportions of the work piece are rereadily lifted in an upward andrearward direction. The hood member I1 is hinged at I82 so that it alsomay be turned upwardly and rearwardly to expose the bufling roll I4. Thepurpose of the hood member I6 is to provide a conduit for drawing awaydust-laden air from the front portion of the buffing roll II just abovethe field of operation on the work piece. In spite of the strong currentof air which tends to remove all dust from the periphery of the buffingtends to be carried around and it is to remove this air that the forwardend of the hood member I6 is carried into close relationship with thesurface of the buffing roll I. An adjustable tongue I86 is provided atthe forward end of the hood member It so lower edge of the tongue I86and the bumng roll may be adjusted, as occasion may require, to securethe best results.

As indicated in a preceding portion of this specification, the slot inthe roll I4 is in a plane at an angle to the axis of rotation of thebuffing roll, the purpose being to eliminate as much as possible abumping eifect that is commonly produced each time that a slot in thecylindrical surface of a buffing roll comes opposite to the roll ll,some of the air with the rotating roll,

work backing portion of a work supporting roll during treatment of apiece of work, it being a well-known fact that there is a noticeablebumping effect in the operation of those bumng rolls which are providedwith a slot parallel with the axis of rotationpf the roll. To insurethat uniformity in the treatment of the work which is so desirable, thebuffing roll I4 is also constantly reciprocated in an axial directionduring its rotation. For this purpose there is provided a forked memberI90 (Fig. l) to engage an end member of the bufling roll I4 fixed to thebuffing roll shaft 24. Said forked member I90 is pivotally mounted atI92 intermediate of its ends upon a bracket extending from the frame ofthe machine. As its other end it is provided with a cam roll I94arranged to ride upon the surface of a cam I96 on a shaft I98 driven bymeans of a pulley 200 and a belt 202 from the power shaft I50. It willbe readily understood that rotation of the face cam I96 will causereciprocation of the forked member I50 and hence of the bumng roll I4.For a more complete description of a mechanism for axially reciprocatinga buffing roll during rotation of the latter, reference may be had toUnited States Letters Patent No. 1,377,434, granted May 10, 1921, uponapplication of L. O. Ramsdell.

In. operating the machine shown in the drawing to buff pieces ofleather, the operator will introduce a piece of leather upon the worksupporting rolls 2 and l and will then depress the treadle I2 bystepping on the tread portion I58. Depression of the treadle causesmovement of the work supporting rolls 2 and l to work presentingposition with respect to the bumng roll II, the treadle, when thusdepressed, also initiating drive of the rolls 2 and l by the chain I34through power means controlled by the clutch I48 (Figs. 1 and 3), andthe arrangement being such that driving movement of the rolls 2 and 4starts just prior to the engagement of the work by the buffing roll 44.It will beobserved that the piece of leather undergoing buffingoperations is fed into the machine progressively during bumng ofsuccessive portions of the leather. When approximately one-half of theleather has been buffed the operator releases the treadle that the spacebetween the which is immediately followed by movement of the worksupporting rolls 2 and 4 away from the buffing roll I4 to an openposition where the leather may be readily reversed and reintroduced toobtain treatment of the untreated portion thereof. Then the operationsmentioned above are repeated to complete the treatment of the workpiece.

Having described our invention, what we claim as new and desire tosecure by Letters Patent of the United States is: V

1. In a buffing machine, a driven cylindrical roll having an abrasivesurface to effect buffing of a surface of a piece of leather, a suctiondevice having an opening adjacent to the abrasive surface of thecylindrical roll to carry away dustladen air, and a brush roll locatedin front of the opening into said suction device and in position tobrush lightly the surface of the abrasive roll, said brush roll havingits bristles in rows alternating with relatively wide spaces between therows whereby at regular intervals during rotation of the brush rolldust-laden air may enter by way of said spaces into the suction means.

2. In a buffing machine, a driven cylindrical roll having an abrasivesurface to effect buffin of a surface of a piece of leather, a suctiondevice having an opening adjacent to the abrasive surface of said rollto carry away dust-laden air, and a brush roll rotated in a directionthe same as that of the abrasive roll, whereby adjacent surfacesof thetwo rolls move in opposite directions, the brush roll having itsbristles in rows spaced substantially from each other, said brush rollbeing of a diameter substantially greater than the correspondingdimension of said opening into the suction device and being located infront of said opening and adjacent to the abrasive surface of thecylindrical roll, each moving row of bristles having an edge which movesin a direction to wipe the leather from the abrasive surface of thecylindrical roll and the spaces between the rows of bristles serving atregular intervals during rotation of the brush roll to permit freeaccess of dust-laden air to the opening into said suction means.

3. In a bufiing machine, a cylindrical roll having an abrasive surfaceto effect bumng of a surface of a piece of leather, a suction devicehaving an opening adjacent to the abrasive surface of the cylindricalroll to carry away dustladen air, and a driven brush roll having itsbristles in straight rows parallel to the axis of the brush roll andspaced substantially from each other, said brush roll being of adiameter substantially double the corresponding dimension of saidopening into the suction device and being located in front of saidopening and adjacent to the abrasive surface of the cylindrical roll,each moving row of bristles having a straight edge which serves to wipethe leather from the abrasive surface of the cylindrical roll and thespaces between the rows of bristles serving at regular intervals topermit free access of dustladen air to the opening into said suctionmeans;

4. In a buffing machine, a buffing roll, a work supporting roll, amember movable about a horizontal axis to carry the work supporting rollin directions toward and from the buffing roll, power means to drive thework supporting roll whereby it feeds the work while at the same timesupporting it against the thrust of the bumng roll, said power meanscomprising a clutch, and a treadle mechanism connected to the lower endof said member and to said clutch and operable to cause said member tomove the work supporting roll into operative relation to the bufllngroll and to control the clutch to initiateoperation oi the driving meansfor said work supporting roll.

5. In a bumng machine, a bufllng roll, a work supporting roll, a membermovable about a horizontal axis to carry the work supporting roll indirections toward and from the builing roll, means to drive the worksupporting roll, said means comprising a clutch, and a treadle mechanismconnected to operate said member thereby to tions toward and from thebufllng roll, said axis.

being about midway of the length of said memher, an idler sprocketmounted adjacent to the lower end of said member, a chain engaging saidsprocket and sprocket wheel. power means to drive the chain whereby thework supporting roll feeds a work piece while at the same timesupporting it against the thrust of the bumng roll, said power meanscomprising a clutch, and a treadle mechanism connected to said memberand to said clutch to cause said member to move the work supporting rollinto operative relation to the builing roll and to operate the clutch toinitiate rotation of the work supporting roll Just before the latterpresents the work piece to the buillng roll.

'1. In a bufling machine, a bufling roll, a work supporting roll havinga sprocket wheel secured thereto, a member movable about a horizontalaxis tocarry the work supporting roll in directions toward and from thebumng roll, idler sprockets mounted on the machine frame adjacent thelower end of said member, a chain engaging said sprockets and sprocketwheel, power means to drive the chain whereby the work supporting rollfeeds the work while at the same time supporting it against the thrustof the bufling roll, said power means comprising a clutch, and atreadle'mechanism connected to the lower end of said member and to saidclutch and operable to cause said member to move the work supportingroll into operative relation to the bufllng roll and to operate theclutch to initiate operation of the driving means for the chain-drivenwork supporting roll.

8. In a bufllng machine, a bufllng roll, a pair of work supporting rollsone of which is movable to a position to back a work piece duringtreatment thereof by the buiilng roll, said work supporting rolls havingsprocket wheels secured thereto, a member movable about a horizontalaxis to carry the work supporting rolls in directions toward and from-the bumng roll, idler sprockets mounted on the machine frame adjacentto and on each side of the lower end of said member, a chain engagingsaid sprockets and sprocket wheel, power means to drive the chainwhereby the work'supporting rolls feed the work while at the same timeone of them supports it against the thrust of the bufilng roll. saidpower means comprising a clutch, and a treadle mechanism connected tothe lower end of said member and to said clutch and operable to causesaid member to move said one of the work supporting rolls into directco-operative relation to the bufllng roll and to operate the clutch toinitiate operation 01' the chain driving means for said work supportingrolls.

GEORGE E. MCLAUGHLIN. WINN E. BROUGHTQN.

